You made a good point Roy. All the trees that I cut are in fairly close proximity to the river that runs around our place, but some of them are inside the flood plain and those grow taller, thicker, and more healthy with wider rings. The ones up on higher ground that grow in rocky soil amonst the cedar trees and are clearly out of the flood plain tend to have tighter rings, are not nearly as tall, or canopies that aren't nearly as thick as the ones growing in the flood plain.
You can also see it in the cedar trees that I have cut down. Good soil, and lots of water will produce more white wood in the cedars that grow really fast, then the ones that grow in rocky ground will have more red wood in the center because they grow alot slower.
Good point, I'm glad you brought that up.